There is a system using a so-called web camera that distributes via the Internet image data obtained by digital capture. In this system, image data to be distributed is stored in a web camera device that has captured it or in a server device that is separately provided. A user who wants to view the image data accesses the web camera device or the server device from a terminal, and receives the desired image data.
In the case of using a planar lens for the lens of the camera device, since the obtained image is a planar image, handling of the image is simple. However, the imaging scope per capture of a planar lens is comparatively narrow. For that reason, by rotating or raising/lowering the camera with a stepping motor that is provided on a platform, the imaging scope is compensated. Patent Document 1 described below discloses a method of a terminal device performing motor-control of the direction of a movable web camera that is provided remotely.
As the lens of the camera device, a wide-angle lens such as a fisheye lens is sometimes used. In the case of using a fisheye lens, since it is possible to cover 180 degrees horizontal and vertical in a single capture, there is no need to frequently move the camera as in the case of a planar lens. In Patent Document 2 described below, a digital camera that adopts a fisheye lens is disclosed. The digital camera that is disclosed in Patent Document 2 shows still images that are captured by the fisheye lens as planar images on a display at the camera rear surface.
In the case of using a planar lens in a camera device of a distribution system, as described above, in order to broaden the imaging scope, it is necessary to frequently move the camera with a stepping motor. For that reason, complicated motor-control that is synchronized with the user terminal becomes necessary. As a result, it is difficult to abbreviate the processing time of the capturing, and there is the inconvenience of stress arising in the user waiting for the distribution.
In the case of using a fisheye lens, the capture scope is expanded each time. However, since distortion appears in the omnidirectional image that is captured, it is necessary to convert the distorted image to a normal image. In particular, in the case of a video, in order to smoothly replay the video, it is required to quickly perform the conversion to a normal image. The method that is disclosed in the aforementioned Patent Document 2 relates to processing of an image that is captured by a fisheye lens. In this process, the captured image is a still image, and no consideration is given to video.
In order to solve such issues, art is known that enhances the convenience of a terminal device that replays a video captured using a fisheye lens (for example, refer to Patent Document 3).